Line-spacing mechanism for a teleprinter or similar printing machine

ABSTRACT

A line-spacing mechanism for a motor-operated printing machine, such as a teleprinter, said mechanism comprising, a differential including a planetary gear drivingly connected to the platen shaft of the machine and at least one sun gear drivingly meshing with the planetary gear, and a clutch drivingly connecting the motor of the machine to the sun gear for imparting rotation thereto, so that the platen of the machine will be rotated in response to selective engagement of the clutch.

United States Patent Cortona et al. [451 Jan. 25, 1972 541 LINE-SPACING MECHANISM FOR A 1,136,223 4/1915 Fraaz 197/121 TELEPRINTER 0 SIMILAR PRINTING 1,158,818 11/1915 Lockwood ,....197/123 I 1,737,801 12/1929 Lyle 1 "197/114 MACH NE 2,131,895 10/1938 Kolm et al .....197/133 [72] Inventors: Alessandro Cortona; Pietro Musso, both of 2, 2, 41 A r h 1 "1 7/127 X Turin, lmly 2,969,729 1/1961 Jackowslu et al .....197/127 X 46, 73 Ass1gnee: Ing. c. 01mm & C.S.p.A., Ivrea 3 3 088 0/1967 Crane 97/84 Turin, Italy FOREIGN PATENTS OR APPLICATIONS 1 1 Filedl 1968 830,668 3/1960 Great Britain ..l97/l33 21 A LN 774 375 I 1 PP 0 Primary ExaminerE1'nest T. Wright, Jr-

Att0rney-Birch, Swindler, McKie & Beckett [30] Foreign Application Priority Data Nov. 16, 1967 Italy ..53754 A/67 [57] ABSTRACT A line-spacing mechanism for a motor-operated printing [52] US. Cl. ..l97/ll4 R machine, such as a teleprinter, said mechanism comprising, a [51] Int. Cl. ..B4lj 19/76 differential including a planetary gear drivingly connected to [58] Field ot'Search ..197/I14,121, 122, 123, 127, the platen shaft of the machine and at least one sun gear 197/133, 84 drivingly meshing with the planetary gear, and a clutch drivingly connecting the motor of the machine to the sun gear [56] References Cited for imparting rotation thereto, so that the platen of the machine will be rotated in response to selective engagement of UNITED STATES PATENTS the clutch 1.080.285 12/1913 Kurowski ..197/123 6 Claims, 5 Drawing Figures PATENTED M25 I972 Fig.4

INVENTOR. NDRO C ALESSA ORTONA PIETRO MUSSO LINE-SPACING MECHANISM FOR A TELEPRINTER OR SIMILAR PRINTING MACHINE BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line-spacing mechanism for a teleprinter or a similar motor-operated printing machine comprising a platen fixed on a shaft rotatable in the fixed frame of the machine and a type carriage movable axially of said platen.

2. Description of the Prior Art Various line-spacing mechanisms for such machines are known, operating by means of a pawl acting on a gear wheel fixed to the platen. These mechanisms are subject to heavy wear and are not suitable for high-speed printing machines.

In a printing machine which is motor-operated and has a platen fixed axially it has moreover been proposed to rotate the platen with the motor of the machine through a clutch. This mechanism, however, requires separate means for turning the platen independently of the motor and the clutch.

SUMMARY OF THE INVENTION These drawbacks are obviated by the present invention, which provides in a teleprinter or similar printing machine operated by a motor and comprising a platen fixed on a platen shaft which is rotatable in the frame of the machine, a type carriage movable along the platen and a line-spacing mechanism for rotating the platen shaft, the improvement wherein the line-spacing mechanism comprises a differential having a planet gear and two sun gears, the planet gear being arranged to rotate the platen shaft and at least one of the sun gears being coupled to the motor by a clutch which, when engaged, causes the sun gear to rotate through a predetermined angle.

The invention will be described in more detail, by way of example, with reference to the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a plan view of a teleprinter incorporating a linespacing mechanism according to the invention;

FIG. 2 is a section on the line II-II of FIG. 1;

FIG. 3 is a section on the line III-III ofFIG. 1;

FIG. 4 is a partial view from above ofa detail of FIG. 2 on a larger scale; and

FIG. 5 is a front view ofa variant of the mechanism accord ing to the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. I, the conventional platen 6 of a teleprinter is fixed on a shaft 7 rotatable in the fixed frame 5 of the machine. The teleprinter is equipped with a carriage 8 carrying a series of type wheels 9 and slidable by means of rollers 11 along a guide 12 parallel to the platen 6.

The line-spacing mechanism includes a bevel gear 13 forming the planetary gear of a differential. The planetary gear 13 is freely rotatable on a pin 14 fixed through a shaft 16 which is rotatable in turn in the frame 5 and is disposed parallel to the platen 6. Fixed on the shaft 16 is a gear 17 which is constantly in mesh via an idler gear 18 with another gear 19 fixed to the shaft 7. The planetary gear 13 is moreover in mesh with two bevel gears 21 and 22 forming the sun gears of the differential. The pinions 21 and 22 are fixed to sleeves 23 and 24 respectively, both rotatable on the shaft 16. The planetary gear 13 and the sun gears 21 and 22 are of equal diameter.

Also fixed to the sleeve 23 is a gear 26 which is constantly in mesh with a gear 27 having a diameter half that of the gear 26. The gear 27 is fixed in turn to a sleeve 28 rotatable on a shaft 29 and forming the driven part of a clutch of the type having a 90 cycle and indicated generically in FIG. 1 by the reference numeral 31. Similarly, to the sleeve 24 there is fixed a gear 32 which is constantly in mesh with a gear 33 having a diameter equal to that of gear 32. The gear 33 is fixed in turn tp a sleeve 34 rotatable on the shaft 29 and forming the driven part of a second clutch similar to the clutch 311 and indicated generically by the reference numeral 36.

The clutches 31 and 36 have driving parts formed by discs 37 and 38 respectively, both fixed to the shaft 29 and having four notches 39 therein (FIG. 2) at from each other. The shaft 29 is rotatable in the frame 5 of the machine and is rotated continuously by an electric motor 10 of the machine.

Each of the sleeves 28 and 34 is normally locked in one of four inoperative positions by a pawl 41 (FIG. 3) which is provided with a projection 42 that engages a corresponding notch 43 in a disc 44 fixed to each of the sleeves 28 and 34. The four notches 43 are disposed at 90 from each other and alternate with four cam surfaces 46 connected to the notches 43 by means of chamfered surfaces 47.

On each of the sleeves 28 and 34 there is also mounted a disc 48 (FIGS. 1 and 2) which is rotatable with respect to the sleeve 28 or 34 on which it is mounted and is provided with four arms 49 disposed at 90 from each other. Each disc 48 is connected by means of a spring 51 to a lug 52 that is integral with a plate 53 fixed to the corresponding sleeve 28 or 34. Formed in the lug 52 (FIG. 4) is a T-slhaped aperture 54. One end 56 (FIG. 2) of a slider 57 is slidable in the horizontal leg 55a of the aperture 54 as seen in FIG. 4, and a lug 58 fixed to the slider 57 is slidable in the vertical leg 55b of the aperture 54 as seen in FIG. 4 and is adapted to engage one of the notches 39 in the corresponding disc 37, 38. The slider 57 has a slot 59 therein which is engaged by a pin 61 fixed to the disc 48 and a slot 62 therein which is engaged by a pin 63 fixed to the plate 53.

The disc 48 is normally urged by the spring 51 against a shoulder 64 of a lever 66 fulcrumed on a fixed pin 65. The lever 66 normally bears, through the action of a spring 67, against a fixed pin 68. In this way, the slider 57 is held by the pin 61 with the lug 58 out of engagement with the corresponding disc 37 and 38, as a result of which the clutches 31 and 36 are disengaged. The lever 66 of the clutch 31 is connected by means of a tie rod 72 to the armature 69 of an electromagnet 71. Similarly, in clutch 36, another lever corresponding to the lever 66 of clutch 31 is connected, by means of another tie rod corresponding to the tie rod 72 of clutch 31, to an armature 73 of a second electromagnet 74. The electromagnets 71 and 74 are energizable individually by means of an electric pulse of brief duration in a well-known manner.

The line-spacing mechanism operates in the following manner.

Normally, the shaft 29 is rotated counterclockwise continuously (FIGS. 2 and 3) together with the discs 37 and 38 (FIG. ll) of the two clutches 31 and 36. To carry out single line spacing, that is to rotate the platen 6 by one step, the electromagnet 71 is energized temporarily. The: armature 69 is then shifted upwardly and, by means of the tie rod 72 (FIG. 2), causes the corresponding lever 66 to turn until it is brought into the dashed line position indicated in FIG. 2. Due to the action of the spring 51, the disc 48 then shifts counterclockwise causing the pin 61 to slide the slider 57 on the pin 63 until the lug 58 bears on the disc 37.

Immediately thereafter the electromagnet 71 is deenergized, as a result of which the lever 66, urged by the spring 67, returns clockwise to the position shown in solid lines in FIG. 2. As soon as the disc 37, as it rotates, then brings a notch 39 into correspondence with the lug 58 of the slider 57, the spring 51 causes the lug 58 to engage the notch 39, thereby causing the initiation of the rotation of the sleeve 28, which is thus rotated through 90 by the disc 37. Correspondlingly, by means of the drive train comprising gears 27 and 26, the sun gear 21 of the differential is rotated through an arc of 45. Since the sun gear 22 is stationary, the planetary gear 13 is now carried along by the sun gear 21 and causes the pin 14 to rotate together with the shaft 16 through an angle which is half the angle of rotation of the sun gear 21, that is through an arc 2230. Consequently, the platen 6 is rotated, via the drive train comprising gears l7, l8 and 19, through an angle equal to one linespacing step.

When the following arm 49 of the disc 48 encounters the shoulder 64 of the lever 66, the disc 48 is locked. The sleeve 28, however, continues its counterclockwise rotation, tensioning the spring 51. The pin 63 pushes the slider 57 so that it rotates counterclockwise about the pin 61. The slider 57 then slides on the pin 63 and the lug 58 disengages the notch 39, the slider 57 thus returning to the position of FIG. 2, as a result of which the sleeve 28 stops. Simultaneously, the projection 42 (FIG. 3) of the pawl 41 engages the following notch 43 of the disc 44, thereby preventing the sleeve 28 from reboundmg.

To carry out double line spacing, that is to rotate the platen 6 (FIG. 1) by two steps, the electromagnet 74 is energized instead. In this case the clutch 36 is engaged for a cycle of 90, similarly to what has been described in the case of the clutch 31. Correspondingly, by means of the drive train comprising gears 33 and 32, the sun gear 22 of the differential is rotated through an arc of 90. Since the sun gear 21 is now stationary, the planetary gear 13 is carried along by the sun gear 22 and causes the pin 14 to rotate together with the shaft 16 through an angle which is half the angle of rotation of the sun gear 22, that is through an arc of 45. Consequently, the platen 6 is rotated, via the drive train comprising gears l7, l8 and 19, through an angle equal to two line-spacing steps.

To carry out treble line spacing, the two electromagnets 71 and 74 are energized at the same time. In this case, both the clutches 31 and 36 are engaged for a cycle of 90. Correspondingly, the sun gear 21, on the one hand, is rotated through an arc of 45 and, on the other hand, the sun gear 22 is rotated through an arc of 90 in the same direction as the sun gear 21. The planetary gear 13 is therefore carried along by both the sun gears, causing the pin 14 to rotate together with the shaft 16 through an angle which is half the sum of the angles of rotation of the sun gears 21 and 22, that is through an arc of 6730. Consequently, the platen 6 is rotated through an angle equal to three line-spacing steps.

According to a variant of the invention, the platen 6 (FIG. is fixed on a shaft 76 which is rotatable in the fixed frame 5 of the machine. Fixed through the shaft 76 is a pin 77 on which is rotatably mounted a bevel gear 78 forming the planetary gear of a differential. The planetary gear 78 is in mesh with two sun gears 79 and 81.

The sun gear 79 is rotatable on the shaft 76 and is fast with a worm wheel 82 in mesh with a worm 83 fixed to a shaft 84 rotatable in the frame of the machine. The shaft 84 is adapted to be rotated cyclically through 180 by means of an electric motor 93, via a clutch 86 adapted to be engaged in a known manner.

The sun gear 81 is also rotatable on the shaft 76 and is fast with a milled knob 87. The sun gear 81 and the knob 87 are connected to a positioning gear 89 by means of a conventional, normally engaged friction clutch, indicated generically by the reference numeral 91. The clutch 91 is adapted to be disengaged by means of an axially movable pushbutton 92. The positioning gear 89 is normally held in a stationary position by means of a spring-biased locking device comprising a roller 88 urged by a spring between two successive teeth ofthe gear 89.

Every time the clutch 86 is engaged, the electric motor 93 of the machine causes the shaft 84 to rotate through a 180 cycle. Correspondingly, the sun gear 79 is rotated by one step via the worm 83 and the worm wheel 82. Since the sun gear 81 is held stationary by the roller 88, the planetary gear 78 is carried along by the sun gear 79 and causes the pin 77 to rotate together with the shaft 76 and the platen 6 through an angle which is half the angle of rotation of the sun gear 79 and corresponds to one line-spacing step of the platen 6.

The platen 6 can moreover be rotated manually to center a line by disengaging the sun gear 81 and the knob 87 from the positioning gear 89. To this end, the pushbutton 92 is pressed axially so as to disengage the friction clutch 91. Immediately thereafter, by maintaining pressure on the pushbutton 92 and turning the milled knob 87, the sun gear 81 is turned through the desired angle. Since the sun gear 79 is now stationary, the

planetary gear 78 is rotated by the sun gear 81 and thus causes the rotation of the platen 6 in the same manner as has been described before, while the gear 89 is held in a stationary position by the roller 88.

We claim: 1. A line-spacing mechanism for printing machines comprising:

a first shaft; motor means for rotating said first shaft; differential means comprising a planetary gear and first and second sun gears each drivingly meshing with said planetary gear; first drive means drivingly connected to said first sun gear; second drive means drivingly connected to said second sun gear; first selectively actuated clutch means interposed between said first shaft and said first drive means for selectively coupling said first shaft to said first sun gear through said first drive means;

second selectively actuated clutch means interposed between said first shaft and said second drive means for selectively coupling said first shaft to said second sun gear through said second drive means; each of said first and second drive means comprising a first gear coupled to the associated clutch means and a second gear connected to the associated sun gear and being operable to impart a predetermined amount of rotational movement to the associated sun gear in response to a predetermined amount of rotational movement of said first shaft upon selective actuation of the associated clutch means, each of said first and second clutch means comprising disc means attached to and rotatable by said first shaft, sleeve means attached to the first gear of the associated drive means and coupling means for selectively coupling said disc means and said sleeve means for a predetermined amount of rotational movement of said first shaft; and

a rotatable platen coupled to said planetary gear, whereby the rotational movement of said platen may be controlled by selectively actuating said first and second clutch means.

2. A line-spacing mechanism for printing machines as recited in claim 1, wherein each of said coupling means includes a locking member disposed about the associated sleeve means and a slider member having first and second positions, said slider member being connected to the associated sleeve means, the position of said slider member being controlled by said locking member, and said slider member engaging the associated disc means in said second position, whereby said first shaft rotates each of said sleeve means during the engagement of the associated slider member with the associated disc means.

3. A line-spacing mechanism for printing machines as recited in claim 2, further including electromagnet means coupled to each of said first and second clutch means for selectively actuating said clutch means, each of said electromagnet means being coupled to the locking member of the associated clutch means.

4. A line-spacing mechanism for printing machines as recited in claim 3, wherein the diameter of the first gear of said first drive means is one-half the diameter of the associated second gear, and the diameter of the first gear of said second drive means is equal to the diameter of the associated second gear, said platen being rotated through an angle corresponding to one line-spacing step when said first clutch means is actuated, through an angle corresponding to two line-spacing steps when said second clutch means is actuated, and through an angle corresponding to three line-spacing steps when said first and second clutch means both are actuated.

5. A line-spacing mechanism for printing machines comprising:

a first shaft;

motor means;

first clutch means interposed between said motor means and said first shaft for selectively coupling said first shaft to said motor means;

differential means comprising a planetary gear and first and second sun gears each drivingly meshing with said planetary gear;

said first shaft being coupled to said first sun gear for drivingly rotating said first sun gear;

a second shaft;

a platen connected to said second shaft, said second shaft being connected to said planetary gear so that when said motor means is coupled to said first shaft by said first clutch means, said first shaft is rotated and produces a corresponding proportional rotation of said platen, said first shaft being rotatable in predetermined angular increments to thereby produce corresponding incremental rotation of said platen;

spring biased locking means coupled to said second sun gear and normally effective for preventing rotation of said second sun gear;

second clutch means interposed between said locking means and said second sun gear and being operative to selectively uncouple said second sun gear from said locking means; and

manual means for operating said second clutch means to thereby manually uncouple said second sun gear from said locking means so that said second sun gear may be rotated to produce a corresponding proportional rotation of said platen, said first sun gear being prevented from rotating in response to the rotation of said second sun gear.

6. A line-spacing mechanism for printing machines comprisa first shaft;

motor means;

a first clutch for selectively coupling said first shaft to said motor means;

differential means comprising a planetary gear and first and second sun gears each drivingly meshing with said planetary gear;

drive means connecting said first shaft to said first sun gear for rotating the first sun gear upon rotation of the first shaft, said drive means preventing said first shaft from being rotated by said first sun gear;

a platen rotatable about a second shaft, said second shaft being connected to said planetary gear;

a wheel having teeth corresponding to line spacing rotational increments of said platen;

a spring-biased locking member normally cooperating with said wheel for preventing rotation of said second sun gear;

a manipulative knob secured to said second sun gear;

a second clutch normally engaged for connecting said knob to said toothed wheel, said second clutch being operable to rotate said toothed wheel by overcoming the action of said locking member, whereby upon engagement of said first clutch, said first shaft rotates said platen via said first sun gear while said second sun gear is prevented from rotating by said locking member, and upon manual rotation of said knob, said knob rotates said platen step by step via said second sun gear while said first sun gear is prevented from rotating by said drive means; and

a manipulative member for disengaging said second clutch to enable said second sun gear to be rotated by said knob for fine angular adjustment of said platen. 

1. A line-spacing mechanism for printing machines comprising: a first shaft; motor means for rotating said first shaft; differential means comprising a planetary gear and first and second sun gears each drivingly meshing with said planetary gear; first drive means drivingly connected to said first sun gear; second drive means drivingly connected to said second sun gear; first selectively actuated clutch means interposed between said first shaft and said first drive means for selectively coupling said first shaft to said first sun gear through said first drive means; second selectively actuated clutch means interposed between said first shaft and said second drive means for selectively coupling said first shaft to said second sun gear through said second drive means; each of said first and second drive means comprising a first gear coupled to the associated clutch means and a second gear connected to the associated sun gear and being operable to impart a predetermined amount of rotational movement to the associated sun gear in response to a predetermined amount of rotational movement of said first shaft upon selective actuation of the associated clutch means, each of said first and second clutch means comprising disc means attached to and rotatable by said first shaft, sleeve means attached to the first gear of the associated drive means and coupling means for selectively coupling said disc means and said sleeve means for a predetermined amount of rotational movement of said first shaft; and a rotatable platen coupled to said planetary gear, whereby the rotational movement of said platen may be controlled by selectively actuating said first and second clutch means.
 2. A line-spacing mechanism for printing machines as recited in claim 1, wherein each of said coupling means includes a locking member disposed about the associated sleeve means and a slider member having first and second positions, said slider member being connected to the associated sleeve means, the position of said slider member being controlled by said locking member, and said slider member engaging the associated disc means in said second position, whereby said first shaft rotates each of said sleeve means during the engagement of the associated slider member with the associated disc means.
 3. A line-spacing mechanism for printing machines as recited in claim 2, further including electromagnet means coupled to each of said first and second clutch means for selectively actuating said clutch means, each of said electromagnet means being coupled to the locking member of the associated clutch means.
 4. A line-spacing mechanism for printing machines as recited in claim 3, wherein the diameter of the first gear of said first drive means is one-half the diameter of the associated second gear, and the diameter of the first gear of said second drive means is equal to the diameter of the associated second gear, said platen being rotated through an angle corresponding to one line-spacing step when said first clutch means is actuated, through an angle corresponding to two line-spacing steps when said second clutch means is actuated, and through an angle corresponding to three line-spacing steps when said first and second clutch means both are actuated.
 5. A line-spacing mechanism for printing machines comprising: a first shaft; motor means; first clutch means interposed between said motor means and said first shaft for selectively coupling said first shaft to said motor means; differential means comprising a planetary gear and first and second sun gears each drivingly meshing with said planetary gear; said first shaft being coupled to said first sun gear for drivingly rotating said first sun gear; a second shaft; a platen connected to said second shaft, said second shaft being connected to said planetary gear so that when said motor means is coupled to said first shaft by said first clutch means, said first shaft is rotated and produces a corresponding proportional rotation of said platen, said first shaft being rotatable in predetermined angular increments to thereby produce corresponding incremental rotation of said platen; spring biased locking means coupled to said second sun gear and normally effective for preventing rotation of said second sun gear; second clutch means interposed between said locking means and said second sun gear and being operative to selectively uncouple said second sun gear from said locking means; and manual means for operating said second clutch means to thereby manually uncouple said second sun gear from said locking means so that said second sun gear may be rotated to produce a corresponding proportional rotation of said platen, said first sun gear being prevented from rotating in response to the rotation of said second sun gear.
 6. A line-spacing mechanism for printing machines comprising: a first shaft; motor means; a first clutch for selectively coupling said first shaft to said motor means; differential means comprising a planetary gear and first and second sun gears each drivingly meshing with said planetary gear; drive means connecting said first shaft to said first sun gear for rotating the first sun gear upon rotation of the first shaft, said drive means preventing said first shaft from being rotated by said first sun gear; a platen rotatable about a second shaft, said second shaft being connected to said planetary gear; a wheel having teeth corresponding to line spacing rotational increments of said platen; a spring-biased locking member normally cooperating with said wheel for preventing rotation of said second sun gear; a manipulative knob secured to said second sun gear; a second clutch normally engaged for connecting said knob to said toothed wheel, said second clutch being operable to rotate sAid toothed wheel by overcoming the action of said locking member, whereby upon engagement of said first clutch, said first shaft rotates said platen via said first sun gear while said second sun gear is prevented from rotating by said locking member, and upon manual rotation of said knob, said knob rotates said platen step by step via said second sun gear while said first sun gear is prevented from rotating by said drive means; and a manipulative member for disengaging said second clutch to enable said second sun gear to be rotated by said knob for fine angular adjustment of said platen. 